“It’s about how you can use short exercises between two and five minutes long to change how you feel, whether that’s to relax when you’re stressed or to create energy when you’re tired.”

Slow, rhythmic breathing may lower blood pressure, according to a review in the journal Breathe in 2017. Meanwhile, a 2015 trial revealed that 20 minutes of rhythmic breathing before bed helped insomniacs to drift off.

And a group of researchers from the Netherlands found that volunteers trained in breath work reported fewer flu-like symptoms after being exposed to a bacterial toxin that can induce a fever, compared to a control group who didn’t do any breathing exercises.

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The breath work group were also found to have lower levels of inflammation after infection, suggesting it could have a beneficial effect on the immune system.

Classes teaching breathing exercises are springing up at gyms across the UK, while workout app FIIT has added a series of breath work videos. Here are some you can try at home.

For instant zen

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Box breathing was originally developed by Japanese zen masters. It breaks down your inhale and exhale into equal parts, like the sides of a box, hence the name. “The length of each part should be whatever feels comfortable to you,” says Richie.

“Start with five seconds but you could lengthen this if you like.” It makes you relax by crowding out other thoughts and focusing you. “By thinking about your breathing, you’re clearing your mind,” says Dr Gavin Sandercock, a sports and exercise scientist and researcher at the University of Essex.

“Most of the time we breathe in for a long time and out very quickly. Exhaling slowly mimics how we naturally breathe while we are sleeping, which is when your nervous system is calm.”

Breathe into your belly through your nose for a count of five seconds.

Hold your breath for a count of five.

Exhale for a count of five.

Hold your breathing for a count of five.

Repeat this pattern for five minutes, or until you have felt yourself noticeably calm down.

For an energy boost

Get your blood pumping and give yourself an instant hit of energy with this technique

Changing the way you breathe can really get your blood pumping. Your heart rate synchronises to the rate of your breathing, explains Gavin. So if you slow your breathing down, your heart beats slower, helping you to feel calm, whereas if you breathe faster than normal it should have the opposite effect. “If you need an instant energy hit, try this,” says Richie.

“Take four quick, powerful inhales through the nose, filling up your lungs more and more with each breath. Then exhale slowly through pursed lips. Repeat this pattern for
two or three minutes.”

For after the gym

This exercise, known as 1-2-1 breathing, can help shift your nervous system from action mode to rest, says Richie, which makes it perfect to aid post-workout recovery. After you’ve finished a tough session your body’s in fight or flight mode, he explains. It should also help you to sleep better afterwards, which is essential for muscle repair after training. The key is your exhalation should be twice as long as the inhalation, followed by a pause.

Place one or both hands over your belly button.

Breathe in through your nose for a count of three. You should feel your hands rise a few centimetres.

Exhale for a count of six and you should feel your hands sink down.

Pause, holding your breath for a count of three.

If that feels easy, extend each part of the breath – so, inhale for four, then exhale for eight, then pause for four. Repeat the pattern for three minutes.

Sources: National Yang-Ming University and Radboud University Medical Centre.

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